14 20
---- = ----- cross multiply
3x x-5
14(x-5) = 3x (20)
14x - 70 = 60x
-14x -14x
-70 = 36x
/36 /36
-70/36 = x
or
-35/18 = x
Answer:
1. -29/156 2. 38/45 3. 29/45 4. 113/24 or about 4.7 5. 457/1, 914/2, 1371/3
Step-by-step explanation:
3/13 - 5/12 can be simplified to 36/156 - 65/156. Subtract this and you get -29/156
4/9 + 2/5 can be simplified to 20/45 + 18/45. Add this and you get
38/45
5/8 - 2/9 can be simplified to 45/72 - 16/72. Subtract this and you get
29/45
3 1/2 + 2 5/12 can be first made irrational to 7/2 + 29/24. This can be simplified to 84/24 + 29/24
113/24 or about 4.7
Not sure about the 457, but to convert it, you multiply it by whatever denominator you have. For example
1x457 = 457/1
2x457 = 914/2
And finally 3x457 = 1371/3
Answer:
18 girls
Step-by-step explanation:
2g = 3b
b = 12
g = girls
b = boys
2g = 3*12
2g = 36
g = 36/2
g = 18
